Electric switch



NoY;. ;6/19zs.' 1,690,780 A. C. GAYNOR ELECTRIC SWITCH Filed Aug. 2. 1926 3 Sheets-Sheet 1 an! fies ltE-I-QQQL A.i c. GAYNOR ELECTRIC SWI TCH- Filed Ana. 2 197.6

Eli Q19,

3 SheetsSheet 2 K; K m

Nov. 6, 192 s. 1,090,750

A. c. GAYNOR I ELECTRIC" SWITCH Filed Aug. 2. 1926 3 Sheets-Sheet -3 Patented Nov. 6, 1928.

UNITED STATES ARTHUR c. GAYNOR, or srnarronnconnncrrcor.

ELECTRIC swrrcn. 4

Application filed August 2, 1926 Serial No. 126,530.

My invention relates to electric switches and has to do, more particularly, with electric switches of the snap type.

One object of my invention is to provide an electric snap switch of such construction as to prevent arcing when the circuit is broken. A further object of my invention is to provide a. snap switch construction such that it can be easily and expeditiously manufacturedand assembled at an exceedingly low bodying my invention. Flg. 2 1s a vertical, sectional view through the switch, taken on the line 22 of Fig. 1. Fig. 3 is a plan view of the switch with the bridge plate and insulating strip removed. Fig. i is a view in end elevation of the operating assembly of the switch removed from the insulating base. i

Fig. 5 is a sectional view, taken on the line 55 of Fig. 4. l I I Fig. 6 is a sectional view taken on the line 6-6 of Fig. 1. Q

Fig. 7 isa sectional view taken on the line 77 of Fig. 2. Q

Fig. 8 is an enlarged perspective view of the bracket which forms a support for the operating parts. l

Fig. 9 is an enlarged the crank shafts Fig. 10 is an enlarged perspective view of perspective view of the actuator lever. v 1

Fig. 11 1s avertical sectlonal view through the aetuztor lever:

Fig. 12 is an enlarged perspective view showing the connection between the. crank shatt and the contact blade.

Fig. 13 is a perspective view showing a modified form of connection between the :crank and the contact blade.

'Fig. 14 is a perspective view showlngan- PATENT OFFICE.

REISSUIED other modified form of connection between the crank and the contact blade.

Fig. 15is a perspective view showing a further modified form of connection between the crank and the contact blade.

Fig. 16-is a perspective View showing a modified form of bracket, which may serve for guiding the floating contact blade into engagement with the contact a-ws, and

Fig. -17 is a plan. View of the blank. from which a contact blade is formed.

In the drawings, the same reference numerals refer to the same parts throughout the several views and the sectional views are taken looking in the direction of the arrows at the ends of the section lines.

vAs stated above, one of the objects of my present invent-ion.is to provide a snap switchconstruction in which arcing will be more efi'cctively prevented than in prior'switches of this type. Opening an electric circuit is attended. in many cases, by a rise in the volt-. age in the circuit adjacent to the point of opening. This is often suificient to overcome the resistance of the air and raise its temperature to such a degree that the current will persist, thereby creating an arc. I propose, in my improved snap switch, to prevent the formation of such an are by providing a mass of insulating material of much greater heat capacity than air and of good heat absorbing qualities locatedvery close to the path which the'contact blade takes as it leaves its engagementwith the contact jaw. I propose to treat the insulating material of the base, or that portion ofit adjacent the contact blade and the contact jaw, .in such a way as to increase its capacity for absorbing heat so that the heat generated by the opening of the circuit; which would otherwise tend to create anarc, is readily absorbed by the portion of the base which is adjacent to such points of contact. I further propose to reduce the tendencv toward arcing by reducing the weight of the moving parts of the switch. thereby increasing the speed at which such moving parts work. By speeding up the contact blade in this way, it may move a suflicient distance from the contact jaws to prevent arcing before suflicient time has elapsed to raise the temperature of the air between the jaws and the retreating blade to a point at wh ch an arc is formed. Snap switches usually include at least two contact jaws, one of which is customarily located near. the bottom of the insulating base and is provided with a vertical lead running from the contact jaw toward the top face of the base. An arc is apt to become established between this vertical lead and the contact blade and I propose to prevent the formation of such an are by interposing a 7 solid insulating barrier between the path of end with a spring seat so that a shaft and the lowerend of this actuator and was an expensive proposition.

movement of the adjacent end of the contact blade and such vertical lead from the contact jaw. To this end,I proposeto provide a laterally'ofi'set recess at the end of the slot in the insulating base, in which the contact blade moves, and to offset the vertical lead from the contact jaw and locate such vertical lead in the offset recess of the base.

In order to reduce the cost of manufacture,

I have provided a snap, switch construction which is made of a few simple parts which can be quickly and easily assembled together.

The crank shaft is made of a piece of wireparts an oscillatory or snap movement to the 1 blade but the blade is capable of lateral displacement with reference to the crank. The

bla de floats, as it were, and is permittedto adjust itself into contact with the contact jaws and the adjustment of these jaws into alinement' with the contact blade is unnecessary. This has the further advanta e that it reduces the cost of and simplifies t e connection between the contact blade and the crank. I further propose to provide means for guiding this floating contact blade into engagement with the contact jaws. For ins:

stance, the base may be so formed as to guide the contact blade into roper engagement with the contact jaws. This simpleand nonrigid connection between thecontact blade and the crank also aids in reducing the weight of the moving parts and thereby speeds up the contact blade and prevents the formation of an arc.

The bracket in which the operating parts are mounted is of very simple construction and may be provided with stop lugh'sturned inwardly to engages. p0 'on of t e crank shaft. I also pro to provide an improved actuator lever which? is formed at ,its lower "ring ma be compressed between the crank o the cran 1ever,,without providing any special formation at either end of the spring for engage ment or connection with the lever or the crank shaft. This reduces the cost of forming the spring as all thatneeds to be done is to form a coil spring of suitable length.

propose to provide an actuator lever which is so formed that the shock incident to limiting the movement of the lever, in one position of by the insulating material which is molded around such metal parts.

I further propose to reduce the cost of manufacture of this switch by eliminating the screws customarily used for mounting the contact jaws in position in the base. To that end, I propose to so form the base and the contact jaws that they are held against all movement with respect to each other except vertical movement and to prevent such vertical movement by means of the bridge plate which extends over these contact. members and clamps them against the base. Similarly, I reduce the cost of construction and assembly by providing the insulating base with a recess or seat in which the top face of the supporting bracket fits and which holds said supporting bracket against movement in a horizontal plane. The bridge plate also extends over this supporting bracketand, being connected to the base, clamps such bracket against vertical movement. a This makes avery simple and cheap construction in which the bracket and the base co-act to limit these elements to vertical movement only and the bridge plate serves as a single member pre venting this vertical movement.

Referring-to the accompanying drawings, in which I have shown a preferredembodfi ment'of my invention, the insulating base 10 is provided with a recess or socket 11, which receives theoperating parts of the switch and or the other, is taken by metal parts instead with a slot 12', communicating with such recess,

andreceiving the contact jaws and movable contact blade. I prefer to make the base of the orcelain and to treat certain portions of the ase, that is, the walls of the slot which receive the contact blade and the contact aws,

by spraying a coating of lacquer thereon in order. to increase the heat absorbing qualities of such parts for the urposes of preventing arcing. I have form however, that a satis-' factory result can be obtained by forming the base of bakelite or of cold molded insulation, 3. material well known on the market andconsisting of a pressed and baked mixture. of itch and asbestos. If the base is made of,

a'kelite, or cold molded insulation, no fur-' ther treatment is necessary inasmuch as it' the necessary heat absorbing qualities for preventing arcing. If porcelain be used however the portion of the base adjacent the path of-the' contact blade should be sprayed with lacquer as described. I have found, further, that the application of acoat base 'ing of paint or paste to such portions of the The insulating base has terminal seats 13 formedthercin and transverse grooves are provided in the top surface of the base, lead ing from opposite ends of the slot 12 to said terminal seats. A hole 14 is provided in each terminal seat to receive the lower end of a binding screw 20. The contactjaws 17 and 21 are located in the slot 12, at opposite ends thereof, the contact jaw 17 being located near the top of the slot while the jaw 21 is located near the bottomthereof. The contact jaw 17 is formed integral with a lead portion 18 which fits in one'of the transverse grooves 15 and is provided with a terminal portion 19 seating on the terminal seat 13. A binding screw is screwed into the terminal portion 19 and projects into the corresponding hole 14. The contact jaw 21, has formed integral therewith a vertical portion 22 which is located in an offset vertical recess 16 formed in the base at the corresponding end of the slot 12, as indicated in Fig. 7. From the upper end of this vertical portion 22 there extends the transverse portion 18 fitting in the corresponding slot 15 and ending in a terminal portion 19 on the seat 13 and receiving a binding screw 20 which projects into the hole 14, as in the case of the contact member at the opposite end of the base. The contact jaw 21 is offset, as at 23, from the lower end of the vertical portion 22.

The operating parts of the switch are supported by a sheet metal bracket comprising a top plate 24, having a central opening 29 therein through which the actuator lever extends, and a pair of spaced depending arms Each of these arms has a bearing 26 formed therein for the crank shaft and is provided with an entrance slot 27 through which the crank shaft may be inserted to its position in said bearing. One of the arms has integral lugs 28 formed thereon, and projecting inwardly toward the opposite arm, which act as stops to limit the oscillatory movement of the crank shaft in said bearing. The shaftis made of a piece of wire bent to the required form and is provided with out turned bearing portions 31 which are journaled in the bearing seats 26 formed in the arms 25 of the bracket 24. The crank portion 32 of the crank shaft is located between the depending arms 25, and the central portion of this crank is bent upwardly to form the hump 33, which provides :nseat for the compression spring 36. It is of considerable importance that the hump 33 should fit snugly within the lowermostcoil of the spring 36. This hump should engage the inside diameter of the spring snugly because if the spring may slip from side to side on the crank, which it would do if it is not snugly supported, this will interfere with the transmission of energy and the crank will not develop suificient speed to break the circuit quickly enough. The wire forming the crank shal't has a lateral projection 34, extending from the end of one bearing portion 31, and a part 35, bent back parallel to the bearing portion 31, which form a non-circular projecting end for said crank shaft, by means of which a non-rigid connectionis made between the crank shaftand the contact blade. The coil spring 36 is compressed between the hump 33 on. the crank portion of the crank shaft and the lower end of an actuator lever 39.- The lower end of said lever has an edge portion 37. of semi-circular outline with a pair of shoulders 38 adjacent the ends of this semi-circular portion, which forms a spring seat for the upper end of the coil spring 36, the semi-circular-portion 3'? of the lever fitting within the end 0 the coil spring and preventing its lateral displacement while thehump 33 on the crank portion fits within theopposite end of the coil spring 36.

The actuator lever 39 comprises a sheet metal member having an upper portion 40 constituting a handle and two laterally extending arms 43. The lower portion 42 of the lever 40' is bent or twisted, as at 41, into a plane at right angles to that of the upper portion of the lever, and this lower portion is formcdwith the semi-circular edge portion and the shoulders to constitute a spring seat,

as illustrated in Fig. 10. The insulation 44 is molded around the sheet metal member constituting the body of the lever and it will be observed that this insulation has a V- shaped recess 45 formed therein, the apex of this V-shaped recess being located in line with the opening 46 which receives the pivot pin for the lever. The edges of the arms 43 are exposed at the outside of the'insulation so that the shock incident to the contact of such arms with the bracket, in limiting the movement of the actuator lever, is taken by the sheet metal member rather than by the insulation.

This actuator lever is pivotally mounted inthe bracket 24. Openings 30 are formed in the depending arms 25 of said bracket, adjacent the top plate thereof, which receive a straight pivot'pin 47 passing through said openings 30-and through the opening 46 in displacement of the pin. When the operat-v ing assembly is mounted in position in the insulating base, the ends of the pivot pin 47 are located adjacent the side walls of recesses 48 and 49 formed in said base and this prevents the lateral displacement ,of said pivot pin.

A seat 5Q, is formed in the upper surface I of the insulating base, of such a sizeand shape that the top plate 24 of the bracket fits therein, and such bracket is held against movement in a horizontal plane by the co nperation of the top plate with such seat. A strip 56 of insulatin material is applied to the upper surface the base and extends across the top plate of the bracket 24 and the contact leads 18 in the grooves 15. A bridge plate 57 is positioned on top of this stri of insulating material and has the usual 0 set endsl58 provided with openings by means of which the switchmay be attached in position. This bridge plate is secured to the insulating base by means of screws 59 extending from the bottom of the base through holes formed thereinand. screwed into said bridge plate. The bridge plate, therefore, serves to clamp the contact leads 18 in the grooves and to clamp the bracket 24 in position in the seat 50, and thereby prevents any vertical movement of such parts.

The contact blade 60 is preferably made from a blank 62 by doubling it over upon itself so as to form a blade of the construction .shown in Fig. 12, having spaced contact portions 61 at each end thereof. I propose further to provide the centralportion of this contact blade with a slot 63 of such size and shape that the non-circular endof the crankshaft, formed by the portions 31,

34 and-35, is received in this slot. This makes a cbnnection which is very simple and which transmits the oscillatory or snap movement of the crank shaft to the contact blade 60 but permits lateral displacemen tof the blade with respect to thecrank shaft, so that the blade floats on the crank shaft and can adjust itself into alinement with the fixed contact jaws 17 and 21.

Instead of the connection shown in Fig. 12, thecontact blade may be provided with two spaced holes 64 and the bearing portion 31 may extend through one of these holes while the portion 35 of the crank shaft extends through the other. By thus weaving the end of the crank shaft through spaced holes in the contact blade, I secure a nonrigid connection which transmits the snap gages the notches 65 and is Wrapped aroundthe central portion of the contact blades Thisprovides a non-rigid connection between the contactblade and the crank shaft by which the snap movement of the crank is transmitted to the blade while-the latter is free to be displaced laterally.

' In Fig. 15, Ihave shown still another modified form of connection between the crank shaft and 'the blade. In this construction the contact blade is insulated from the crank shaft. Pieces 71 of insulatin material are located on oppositesides of the central portion of the contact blade and areclamped against the blade by means of the members 68 and 69 the latter having overhangin flanges 70, which are bent over in front of the plate 68. The end 67 of the hearing portion 31 of the crank shaft has a noncircular formation which fits in non-circular holes in the plates 68 and 69. An enlarged hole is provided in the contact blade 60 through which this portion 67 passes without touching, so that'the crank shaft is adequately insulated from the contact blade.

It will be observed that the contact blade 60 is of double formation,providing at each end a pair of resiliently spaced contact memblade as to bring the contact members thereon into proper cooperation with the contact jaws in said slot. In Fig.- 16, I have shown a modified construction of the bracket 24,

which serves the function of guiding the floating contact blade 60 so as to bring it into proper cooperative relationship with the fixed contact jaws mounted on the base. In this modified construction, one side arm 25 of the bracket 24 has a flange 72 turned upwardly therefrom and spaced from said arm so as to provide theslot 73 between said arm and said flange. The contact blade 60 works in said slot and is guided thereby. The flange 72may be provided with an entrance notch 74 which permits the assembly 'ofthe parts and. gives passage tothe end of the crank shaft during" such assembly.

The operation of this switch construction should be apparent from the foregoing description. In Fig. 2, the parts of the switch are shown in position to close the circuit between the contact j aws' 17 and 21. When the operator wishes to break the circuit, he moves the actuator-lever 39 from the position shown in Fig. 2 to the right. This causes the lower end ofthe actuator lever to move from right to'left and, since the spring seat 37 formed at the lower end of this lever acts upon. the upper end of the spring 36 and compresses it between said seat and the crank portion of the crank shaft, the movement of the lower end of the actuator lever, from right to left will first tend to compress more strongly the spring 36 and then, as the lower end of the actuator lever passes the center line, this compressed spring will act upon the crank portlon of the crank shaft 31 and impart a snap movement of oscillation thereto, which ment with the contact .jaws '17 and 21. A movement of the actuatorlever fromright to left will correspondingly impart a snap movement to the crank shaft and the contact blade mounted thereon, which will carry the contact blade into engagement with the jaws and ,close the circuit once more.

It will be noted that the walls of the slot 12 are close to the path of movement of the contact blade 60. When the circuit is broken, there is a tendency for the creation of an are between the end of the contact blade and the adjacent contact jaw but the walls of the slot are located so close to the path of movement of the contact blade and are formed of material having such \heat absorbing qualities that the heat is absorbed by the walls of the slot and the air does not increase in tem perature to a point sufficient to create an arc. Furthermore, the Weight of the moving parts is greatly reduced by the form of the connection between the contact blade and the crank shaft and consequently these parts can move more rapidly than ifthey were heavier. The result. is that the increased speed of movement of the contact blade also aids in preventing the formation of an are. There is also a tendency for the formation of an are between the end of the contact blade and the vertical lead portion 22 connected with the lower contact jaw 21, but I have prevented thisby placing such vertical lead portion in the offset recess 16 at the end of the slot 12. Consequently, the corner or shoulder formed at the edge of the recess 16 is interposed as a solid barrier of insulating material between said vertical lead 22 and the path of the contactblade (30 and prevents arcing at this point.

The cooperation of the transverse portions 18 of the contact members and the transverse grooves '15 in the base serves to prevent any movement of these contact jaws lengthwise of the slot 12. Movement of these contact jaws transversely of the slot is prevented by the projection of the binding screws 20 into the holes 14 of the'terminal seats. The vertical movement of the contact jaws in the slot 12 is prevented by the clamping action of the bridge plate 57 which confines the contact members against vertical movement. This makes, a very simple and cheap assembly which eliminates two fastening screws customarily employed heretofore for the purpose of fastening the contact jaws to the base.

The bracket 24 is seated in the seat 50 formed at the upper surface of the insulating base, and this seat confines said bracket against movement except in a vertical direction. The bridge plate serves to clamp this bracket, and the operating parts carried thereby, against vertical movement so that this provides a very simple and cheap construction in which the assembly can be performed very quickly and expeditiously and the parts securely clan'iped in place merely by" screwing the bridge plate in position.

The connection between the contact blade and the crank shaft is an exceedingly simple one. Unlike prior constructions, no effort has been made to connect the contact blade rigidly with the crank shaft. The connection between the contact blade and the crank shaft is such as to transmit oscillatory or snap movement from the crank to the blade, but the blade floats upon' the crank shaft, that is, it is free to be displaced laterally with respect thereto. VVherev'er, in the specifica- 'tion or claims, I refer to the contact blade floating upon the crank, I mean a connection between the blade and crank having the above characteristics.

This results in economy in material as it eliminates the comparatively expensive element usually-provided for fasteningthe contact blade to the crank shaft, lightens these parts, and, further, provides a construction in which it is not necessary to adjust the fixed contact jaws into alinemcnt with the contact blade, as this blade floats upon the crank shaft and adjusts itself, with the aidof the slot formed in the base, into alinement' with the said contact jaws.

Certain features of my invention are not limited to use in snap switches but may be used in connection with other electric switches. In so far as my invention is applicable only to snap switches, it is not to be limitedto snap switches which are actuated by a lever as many features of it are also applicable to snap switches of the type which are actuated by a rocker member under the control of push buttons, for instance. Many features of my invention are also applicable to three-way and four-way switches, although in this particularinstance I have described my invention as embodied in a two-way switch.

I am aware that my invention is susce tible of considerable variation without eparting from the spirit thereof and, therefore, I desire to claim the invention broadly as indicated by the appended claims.

What I claim is: v

1. In a snap switch, the combination of a bracket, a wire crank journaled thereon,'one end of said crank being doubled back upon itself, operating means including a spring for imparting an oscillatory movement to said crank, and a contact blade having a slot receivim said doubled back end portion of the crank. v

2. In a snap switch, the combination of a baseof insulating material having a recess to receive the operating parts and a slot communicating with said recess, fixed contacts located in said slot, a bracket, a crank jourlilll naled thereon, operating means including a spring for imparting osclllatory movement to said crank, and a contact blade so connected to said crank as to receive oscillatory movement therefrom but free to be displaced laterally, the Walls of said slot serving to guide said blade into operative engagement with said contacts.

' 3. In a snapswitch, the'combination of a base of insulating material, fixed contacts carried thereby, a bracket, a crank journaled thereon, o crating means including a spring for imparting an oscillatory movement to sai crank, a double contact blade cooperating with said fixed contacts, said double blade being so connected to said crank as to receive oscillatory movement. therefrom but free to be displaced laterally, and means for guiding the said double blade into engagement with said contacts.

4. In a snap switch, the combination of a bracket, a crank shaft journaled thereon, a contact blade carried by said crank shaft, an actuator lever having a body of sheet metal the lower portion of which is twisted into a plane at right angles to the upper portion and provided with a spring seat, saidlever being pivoted upon said bracket, and a spring compressed between the spring seat and the 6. In a snap switch, the'combination of a bracket, a crank shaft journaled thereon, a contact blade carried by said crank, an actuator lever pivoted on and extending through said bracket and including a sheet metal body having a depending lower end provided with a spring seat and laterally projecting arms adapted to contact with the lower face of the bracket to limitmovement of said lever, and insulation molded about the upperportion of said sheet metal member including the arms,

and a spring compressed between the spring seat and the crank portion of said crank shaft. 7. In a snap switch, the combination of a bracket, a crank shaft journaled thereon, a contact blade carried by said crank shaft, an actuator lever pivoted on and extending though said bracket and including a sheet metal body having a depending lower end. with an arcuate edge provided with shoulders at each end thereof to form a spring seat, and a spring interposed between the spring seat and thecrank portion of said crank shaft, said arcuate portion of the actuator lever projecting into the helix of the spring to prevent displacement thereof. I

8. In a snap switch, the combination of a base of insulating material having a recess therein, an operating assembly including a bracket, a crank journaled thereon,'a spring.

and an actuator lever pivoted on said bracket, the walls of said recess engaging the bracket to prevent horizontal movement thereof, and abridge plate fastened to the base and extending over said bracket to prevent vertical movement thereof. 1 i

9. In a snap switch, the combination of a base of insulating material having a recess therein, an operating assembly including a bracket, a crank journaled thereon, a spring and an actuator lever pivoted on said bracket, the walls of said recess engaging the bracket to prevent horizontal movement thereof, a strip of insulating material applied to the upper surface of the base and extending over said bracket, and a bridge plate fastened to said base and clamping said strip of insulating material in position over said base to prevent vertical movement of the bracket with respect thereto. I

10. In a snap switch, the combination of a base of insulating material] having a recess therein provided with a seat surrounding the upper edge of said recess, an operatingassembly lncluding a bracket, a crank journaled ote'd on said bracket, the top plate of said bracket fitting said seat and held against horithereon, a spring and an actuator lever piv- 

